Jitter is defined as deviations of signal edges from their ideal positions in time. Jitter characterization is an integral part of performance qualification for a wide variety of application, such as wideband serial communication (SONET, SDH), high-speed serial input/output (IO) devices (HyperTransport, PCI-Express, Infiniband, RapidIO), and timing circuits including clock generators, and data recovery units. In serial communication applications, jitter affects the link bit-error-rate (BER), which is a key performance parameter.
To qualify this impact, it is necessary to decompose jitter to its various components, because each jitter type has a different effect on BER. Different types of jitter include, Random jitter (RJ), Data-dependent jitter (DDJ), Duty-cycle distortion (DCD), Periodic jitter (PJ), and Bounded uncorrelated jitter (BUJ)
While various methods have been used for measuring jitter components including the use of spectrum analyzers, oscilloscopes (both real-time and undersampling), bit-error rate analyzers, and time interval analyzers (TIA), no design has emerged that generally encompasses all of the desired characteristics as hereafter presented in accordance with the subject technology.
In view of the recognized features encountered in the prior art and addressed by the present subject matter, an improved measurement methodology based on continuous time interval analyzers (CTIAs) has been provided. A continuous time interval analyzer (CTIA) is an attractive solution because it can provide high bandwidth, fast measurement, and excellent accuracy.